Ask question

Ask question

All categories

andrew-mc [135]

3 years ago

5

A boat crosses a river of width 244 m in which the current has a uniform speed of 1.99 m/s. The pilot maintains a bearing (i.e.,

the direction in which the boat points) perpendicular to the river and a throttle setting to give a constant speed of 1.68 m/s relative to the water. How far downstream from the initial position is the boat when it reaches the opposite shore

1 answer:

vovikov84 [41]3 years ago

5 0

Answer:289.02\ m

Explanation:

Given

width of river $d=244\ m$

velocity of current $v_1=1.99\ m/s$

Velocity of boat w.r.t to current $v_{21}=1.68\ m/s$ perpendicular to current

therefore Perpendicular component of velocity will help boat to cover the width of river in $t_1$ time which is given by

$t_1=\frac{244}{v_{21}}$

$t_1=\frac{244}{1.68}=145.23\ s$

In this time current will drift the boat a distance of

$x=v_1\times t_1$

$x=1.99\times 145.23$

$x=289.02\ m$

You might be interested in

Describe the point at which the kinetic energy of the pendulum is the highest

Arlecino [84]

The highest point<span> of the </span>pendulums<span> swing is when the potential energy is at its </span>highest<span> and the </span>kinetic energy<span> is at its lowest.</span>

5 0

3 years ago

Describe how one plays Dr.Dogeball

JulsSmile [24]

•To play Dr. Dodgeball you need to have 2 teams to verse each other.
•Next, select one person from each team to be the doctor (depending on the size of the teams you can have varying amounts of doctors)
•Continue to play dodgeball how you normally would
•When a player gets hit and is “out” they have to sit on the ground and wait for the doctor to “revive them” (this usually requires the doctor dragging,touching, or moving the player that is out to a “revival place” which is usually decided on by the advisor or person in charge.
•Finally, try to get all the doctors and players out from the other team. Get the doctors first, for they cannot revive themselves. Which means the other players are out after they get hit with a ball since the doctors are out. (Some games are played where if all doctors are out the game ends)
Hope this helped! Play on! And plz mark brainliest lol this was long to write :D

4 0

2 years ago

Which scenarios are examples of physical changes? Select three options

pashok25 [27]

Answer:

A kid becoming an adult

A leg becoming bruised

A person's blood pressure raising because they are running

need a picture to answer specific questions.

Explanation:

All of these are physical changes. Hope that this helps you and have a great day :)

4 0

2 years ago

A horizontal pipe of diameter 1.03m has a smooth constriction to a section of diameter 0.618 m. The density of oil flowing in th

vodka [1.7K]

Velocity of the oil in the pipe: 0.76 m/s, in the constricted section: 5.87 m/s

Explanation:

We can solve this problem by using Bernoulli's equation:

$p_1 + \frac{1}{2}\rho v_1^2 = p_2 + \frac{1}{2}\rho v_2^2$ (1)

where

$p_1 = 7340 N/m^2$ is the pressure in the pipe

$p_2 = 5505 N/m^2$ is the pressure in the constricted section

$\rho = 821 kg/m^3$ is the density of the oil

$v_1$ is the velocity of the oil in the pipe

$v_2$ is the velocity of the oil in the constricted section

Also, according to the continuity equation,

$A_1 v_1 = A_2 v_2$

where

$A_1 = \pi r_1^2$ is the cross-sectional area of the pipe, with

$r_1 = \frac{1.03}{2}=0.515 m$ is the radius

$A_2 = \pi r_2^2$ is the cross-sectional area of the constricted section, with

$r_2=\frac{0.618}{2}=0.309 m$ is the radius

So the equation becomes

$r_1^2 v_1 = r_2^2 v_2$

So we can write

$v_2=\frac{r_1^2}{r_2^2}v_1$

Substituting into eq.(1),

$p_1 + \frac{1}{2}\rho v_1^2 = p_2 + \frac{1}{2}\rho (\frac{r_1^2}{r_2^2}v_1)^2$

And solving the equation for $v_1$ :

$p_1 + \frac{1}{2}\rho v_1^2 = p_2 + \frac{1}{2}\rho \frac{r_1^4}{r_2^4}v_1^2\\v_1=\sqrt{\frac{p_2-p_1}{\frac{1}{2}\rho-\frac{1}{2}\rho \frac{r_1^4}{r_2^4}}}=0.76 m/s$

And the velocity in the constricted section is

$v_2=\frac{r_1^2}{r_2^2}v_1=5.87 m/s$

Learn more about flow rate:

brainly.com/question/9805263

#LearnwithBrainly

7 0

2 years ago

A large crate of mass m is placed on the back of a truck but not tied down. As the truck accelerates forward with an acceleratio

Andrew [12]

"Force of friction between the crate and the floor of the truck" is the one force among the choices given in the question that <span>causes the crate to accelerate forward. The correct option among all the options that are given in the question is the third option or option "c". I hope the answer helps you.</span>

4 0

3 years ago

Read 2 more answers